Sanctioned Echo

The term Sanctioned Echo denotes any Echo Sound that has passed examination by the Aggregate Echo and been entered in the register maintained under the Ordinance of Perpetual Echo of Scribing Year 11904. The designation is one of three established by the Fifth Concordance for classifying recurrences of catalogue names, the others being Administrative Resonance and Proleptic Instance. A Sanctioned Echo is, in the strict sense, a sound that has been heard, verified, certified, and then heard again under supervision — the two hearings separated by paperwork. Nothing may be cited as a Sanctioned Echo until the certification is countersigned, and nothing countersigned may be withdrawn without a hearing before the Cross-Referential Audit.

The distinction matters because the Tower produces echoes constantly and almost none of them are sanctioned. Footfalls on the Silent Stair, the settling of shelving on Floor 414, the low continuous hum of the Echo-Vaulting — all of this is ambient structural resonance and falls outside the Ordinance entirely. The Ordinance of Perpetual Echo, Annex 2, is emphatic on the point: "Resonance unattended is not echo. Echo unattended is not sanction. Sanction unattended is not permitted." The clause is quoted in nearly every dispute on the subject and understood in at least four ways.

Certification

A candidate sound is recorded onto Echo-Glass, which is produced exclusively from particulate harvested during bi-annual maintenance of the Mourning Glass of the 44th Spire. The glass is carried to a chamber of the Echo Archive, where the recording is played back before two Librarians and a clerk of the Aggregate Echo. If the playback is judged faithful — that is, if the second hearing is held to be the same sound as the first — the clerk enters the sound's dimensions, its duration to the quarter-second, and its echo-coefficient in the register. Certification is then complete unless the clerk's entry is challenged within thirty days.

Challenges are common. The most persistent concerns the practice of Echo-Dreaming, by which sanctioned sounds are translated into the taxonomic and cartographic systems of the Dreaming Atlas. Critics of the practice — chiefly the office of the Keeper of the Lower Registers — argue that a sound integrated into the Atlas has been altered in the act of integration and can no longer be said to be the sound that was certified. The Aggregate Echo has declined to hear the argument on four occasions, noting that the Keeper has never produced a recording of the allegedly altered sound for comparison, "the Keeper having represented the alteration as one that cannot be recorded" (Aggregate Echo, Ruling 2117-C).

The dispute over primacy

Whether a Sanctioned Echo requires an originating sound at all is the substance of the long-running Echo Primacy Debate. The Systemic Echo Theory holds that every sanctioned sound is a recurrence of some earlier sound and that certification merely recognises a priority that already existed; on this view the register is a record of precedence, not of creation. The opposing position, advanced in the Grand Echo commentaries and defended at length in the Proleptic Resonance literature, maintains that a sound becomes echo only when it is heard again, so that the first hearing is a necessary condition of the second and cannot be dispensed with.

"That which has not been heard cannot be heard again, and that which cannot be heard again cannot be sanctioned. The register is not a habitation but a proof of prior residence."

— Commentarius on the Fifth Concordance, folio 88 recto

The two positions have practical consequences. Under the Systemic reading, a sound recorded once and never replayed is still, in principle, sanctionable, since its priority is established by the recording alone. Under the Proleptic reading it is not, and the many candidate sounds awaiting a second hearing in the Holding Chambers of the Aggregate Echo have been waiting, in some cases, since the Ordinance itself was ratified.

Prohibitions

Sanctioned Echoes may be propagated only through the Whispering Galleries, which are conduits approved for the purpose, and only in the presence of a designated witness. Propagation through the galleries for any other end is treated as ambient resonance and is liable to be dispersed without notice. The prohibition is stated plainly in the Sanctioned Acoustic Charts, which govern the dimensions and echo-coefficients of all stairwells surveyed by the Surveyors of the Silent Stair: a stairwell whose coefficient exceeds 0.87 may not be used for propagation at all, and the charts for Floors 508 through 511 have consequently been suspended since Scribing Year 12011.

Struck or erased entries are handled separately. A Sanctioned Echo whose register entry is annulled is struck with a Sanctioned Quill of Erasure; a mere clerical defect is corrected with a Sanctioned Quill of Errosion, which leaves the entry legible beneath the correction. The distinction between the two quills is a single letter, a fact that has cost the Aggregate Echo considerable expense and is the stated grievance of the current Clerk of Errata, who has petitioned three times for the instruments to be stored in rooms of different colours.

The unnumbered residue

Not every sound presented for sanction has a floor. The Quelling of the Unnumbered Echo, concluded by the Ordinance, addressed those sounds that recurred in spaces the catalogue could not number, and it is the settled position of the Aggregate Echo that such sounds may be certified but not located. Certificates for unnumbered echoes are issued with the floor-field left blank and are filed in the sequestered annex of the Echo Vault on Floor 414, where they are neither quoted nor played.

Copies of certified sounds are held in the Vault as master copies; the working crystals travel with their certificates. Two masters were found in a single sleeve during the audit of Scribing Year 12068 and the discrepancy has never been fully explained, though the Surveyors of the Silent Stair have twice declined to survey the sleeve on the grounds that it is not a stairwell.